Spark-plug tester.



lA. DE GLAIRMONT. SPARK PLUG TBSTR. APPLICATION FILED NOV. 28, 1910.

Patented Jau 9, 1912.

I. u1, W G

Cyr

'il i y rricn.

ADOLFO DE CLAIRMONT, OF TOLEDO, OHIOl SPARK-PLUG TESTER.

Specification of Letters Patent.

Application filed November 28, 1910. Serial No. 594,598.l

To all whom it may concern.'

Be it known that L-ApoLFo DE CLAiRMoNT, a citizen of the United States,residing at Toledo, in the county of Lucas and State of Ohio, haveinvented certain new and useful Improvements in Spark-Plug' Testers, ofwhich thefollowing isa specification.

This invention com'rehends certain new and useful improvements inaccessories for internal combustion engines of automobiles andthe like,and relates particularly to a device for testing the spark plugs of theengine or motor, being especially designed for a motor embodying morethan one cylinder as is almost universally adopted at the presentl time,and where, without the use of a test-- ing'l device such as I haveinvented, the owner of an automobile or the meclianiciaii is p ut toconsiderable trouble to determine which cylinder is missing.

Without the use of a device of this character, it is obviouslynecessary, in order to finda cylinder that is missing owing to adefective spark plug', to go to the vibrator and test out the defect-ivecylinder, or short circuit th'e sparkfplug connections on all of thecyliners except one, each cylinder being thereby tested in turn todetermine in which one the charge fails of ignition.

I am aware that it has been proposed' to provide devices for testingspark plugs, said devices being designed to be applied to a .plug so asto form a visible spark crossing a gap provided for that purpose, butmost of these devices as heretofore constructed have been open to thesame'objection Athat is incidental to that method of testing a sparkplug' by unfastening one of the connections to provide aA gap acrosswhich thecurrent might jump to produce a spark, namely that the spark isthusproduced in the open air with the attendant danger of igniting thegasolene vapors which are liable to be collected or generated around thecarbureter and other exposed parts of a gasolene motor.

/Vith the knowledge. of these conditions my invention has for itsprimary object a 'very simple instrument simple and eiiicient device fortesting spark plugs, the same being provided with an inclosed gapvisible through a glass or other inclosed element, whereby the spark maybe at once lseen if produced, without the eX- posure and danger abovereferred to. And the invention has for a further object a of thischaracter 1n order to ascertainV which may be easily and instantly to aspark plug without the necessity of even temporary connection thereto,maybe composed of comparatively few 'parts that may' be easily andcheaply inanufactured and readily assembled.

arrangements and combinafully describe and claiml For a fullunderstanding o reference is to be had to the scripticn and accompanyingwhich: V Figure 1 is a longitudinal sectional View of a spark plugtester constructed in iccord-v ance with my invention; Fig. 2 is aperspective view of the body portion of the device; and, Fig. 3 is a.transverse section thereof. Corresponding and like parts are referred toin the following descriptionl and indicated in all the views of thedrawing by the same reference characters.

'My improved spark plug tester embodies plates l and 2 that are composedof -any the invention following dedrawing, in

disk 4, passing through a preferably cylindrical plug 5of rubber or someother insulating substance. The end plate 2 is correspondingly formedwith a stem 6 which is tapered at its inner end to a point, as indicatedat 7, said point being disposed centrally to the inner face of the disk4 and in close. proximity thereto, but spaced therefrom suiiiciently toform a gap. The stem 6 passes through an insulating plug 8 similar tothe plug 5. The plate 2 is formed .with a preferably interiorlythreadedboss 9 designed for the receptionof one end of a handle 10 of Wood orthe device. closed in a tube 1l preferably formed of glass or some othertranslucent substance, whereby the spark produced at the gap between thedisk and point may be easily viewed, without the dangers that accompany4an exposed spark. The outer end plate l is formed with a' laterallyprojecting portion, preferably recessed at vits edge, as indicated at12, and the innermost end these and other objects in view 'as A l thelike, whereby to secure the handle to the body portion of The disk 4vand point 7 are in Patented Jan.. 1912.

applied L l and lwhich parts that I shall hereinafter tending inlongitudinal alinement with each other with adjoining ends in closeprox- 30 imity but spaced from eac other insnlat' g plugs throughWhicl/rthe/pngegend, anda translrfre. l surrounding said stems plate 2is correspondingly extended laterally, but farther than the end plate l,the laterally projecting lside of the end plate 2 being forked, asindicated at 12a.

ln the practical use of myimproved spark plug tester, the recessedoutermost end arideonnected to said plugs.` 1 is applied to theloVa/sempertien/or the plug 2. A spark plug tester, comprising end 35lc" 'testedwiil the forked end plate plates each of`which is formed witha latapplied to the neck of the spark plug Where eral extension, oneextension bein g extended are .located the vWiring connections with thefarther than the other, the shorter extension lbattery or magneto. Thetester is merely 'being'forrncd with a-reces'sed edge and the formed inthe respective end plates and exapplied to` the plug, being grasped byvthe longer extension with a fork, stems formed 40 handle 10 and it isnot necessary to even in the respective end plates and extendingtemporarily attaclrthe tester to the plug. in longitudinal alinementwith each other lt the plug is Working, it is obvious that withadjoining ends in close proximity but when the tester isapplied therewill .immespaced from each other, insulating plugs diately appear aspark inside ot the tube 1l through which the stems extend, and a 45showing that the spark plug is in Working translucent tube surroundingsaid stems and y order. connected to said -plugs the innermost endHaving thus described the invention, plate being formed with a boss,and'a handle what is claimed is: l of insulating material. secured tosald boss.

\ In testimomr whereof, I aitix my signature l. A spark. plug tester,comprising end l plates each oit which is formed with a lateralextension, one extension being extended Jarther than the other, theshorter eXtension being formed withl a recessed edge and Witnesses:

'n presence of two witnesses.

A'notro E erlnauor'r.- a. 8.1"

the longer extension Vwith a fork, stems E, M. KENATH,

vRA)v HARPER.

